The study of aphasic patients' word-learning skills in particular and lexical knowledge in general will be pursued. New, low frequency words will be taught to aphasics in order to characterize the strategies they employ to learn about words, and to specify the types of lexical information which are eventually remembered by patients. In particular, assessments of semantic and grammatical information will be conducted. These findings will be examined in comprehension and production tasks with known lexical material as well. Specific topics include: A detailed understanding of the different lexical semantic hypotheses developed by Broca's aphasics and fluent aphasics; further exploration of the interaction between semantic and grammatical information represented by a single word; and additional evidence for Broca's aphasics' lexical grammatical savings and deficits in known and novel, non-linguistic domains. Additionally, knowledge of functors in aphasia will be investigated by exposing patients to new nouns couched in phrases with different known functors. For example, the ability to distinguish between a common noun and a proper noun on the basis of the presence/absence of an article, the capacity to modify grammatical judgments as a function of semantic context, the ability to distinguish between the definite article 'the' and the indefinite article 'a', and the capacity to distinguish between a known article 'a' and an anomalous article 'ba' will be explored.